The present invention pertains to halogenated elastomers and more particularly pertains to methods for halogenating rubbers while dissolved in an organic solvent.
Present methods and techniques for mixing and distributing gaseous halogens into high viscosity rubber solutions for halogenation of the rubber are generally on the batch basis and involve use of high energy input devices such as turbine mixers and fully baffled vessels. The mixing vessels are frequently glass lined kettles which are massive, expensive and equipped with elaborate hydraulic drive units. The procedure employed with such gas-liquid mixers is to add high viscosity rubber solution, begin agitation, and proceed with injection of the gaseous halogen over a prolonged period of time. Since the process is essentially a batch operation, much of the reaction occurs in such a manner that the concentration of the halogenated rubber being produced in the solvent is subject to variation, and this has an adverse affect on the quality of the product produced. In addition, it is difficult to duplicate process conditions for halogenating the rubber from one batch to the next.
It is therefore an object of the present invention to provide a process for halogenating elastomers whereby an elastomer can be halogenated continuously at uniform process conditions.
Another object of the present invention is to provide a process for halogenating elastomers while dissolved in an organic solvent without resort to extensive mechanical agitation of the rubber solutions.
Other objects and advantages of the present invention will become apparent from the following description and the appended claims.